Copier

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The copy machine is next to the camera and projector , a basic unit of film technology. Film copying machines are used for the production of

  • Samples, the first positives from fresh originals;
  • Duplicates, be it entire roles of a production, be it sections for assembly, i.e. security elements, and
  • Copies for the performance or broadcast, i.e. elements of reproduction.

A basic distinction is made between continuous and intermittent copying processes , in turn the contact and optical methods , so that there are four typical copying machines.

In constant contact, cheap bulk copies are made, mostly with a fixed light: single-light positives. Intermittently in contact, one creates duplicates, because the frame chain is only preserved with a film that is fixed frame by frame. Mass reductions such as four 8-mm films from a 35-mm or a 16-mm original are created continuously optically. Optical trick copying machines function intermittently for image enlargements, for example from 16 mm narrow film to normal film .

Since these systems consist of one or more projectors and a camera, which can be repetitively shifted against each other with an accuracy of hundredths of a millimeter, enlargements of sections are possible, but also all conceivable circuits thanks to separate controls. These include freeze frame, stretching (roughly each image copied twice), gathering; Picture reversed, upside down, tilting, etc.

Copy machines often have to meet two contradicting technical requirements, namely great precision and high speed. When producing short duplicate sections, such as fades, fade-ins, etc., frame rates of 4 to 6 per second are sufficient. However, a 100-minute film, of which perhaps 3,000 prints are supposed to run on the same day, must exist in several duplicates in different locations. From five balanced internegatives, possibly more, copyists pull hundreds of positives in a few days at twenty times the speed (over nine meters per second).

In addition to the image copying machines, there are also some for photographically recorded sound recordings , the so-called soundtrack. In the second half of the 1930s, the sound copying machines were developed into so-called slip-free sound copying machines. This state of the art has remained unchanged to this day.

Development of copier machines

The film pioneers copied with the camera by simply removing the lens, clamping the negative and raw material layer on layer and using the light from a lit white wall. This enabled high quality prints to be produced. There is almost nothing that can be improved on this principle. Illustrations in this regard are known by name from the Lumière , Lyon. At Edison, Dickson and Krüsi built a gear-wheel copier from 1891-92, the continuous process , the contact method . An illuminated slit the width of a picture was enough.

With the rapid industrialization of cinematography from 1898, the first generation of copier machines was also built. It consists of a combined lamp housing and film drive, holders for the starting and raw material, an electric motor with a belt for the drive shaft and a basket provided. Ordinary low-voltage light bulbs were used to make them last a long time. A light control was only hesitantly installed here and there. The cameramen between 1888 and 1908 were mostly photographers who knew exactly how to expose. The originals were rarely exposed more than half an aperture incorrectly.

The almost explosive spread of the film led to solid, resilient copying machines, the best known of which came from France, the Matipo by Debrie . The name arose from the words Machine à tirer les positifs . After the First World War, it was delivered in a dozen variants, but all of them had a housing made of light metal casting. The mechanism was characterized by the generous dimensioning of its parts. The copyist oiled the Matipo just as generously, which rested on a cast base and ran at around 12 frames per second. Similar systems from Arnold & Richter or Agfa in Germany were in operation until the 1970s and 1980s, mostly equipped with the subtractive color filter systems offered. For preparation for copying, see Film Light Determiner .

The US film market has been uniform since 1914. The seemingly cozy European step contacts disappeared there in favor of simple, robust slotting machines. Bell & Howell, Chicago, was a leader in this field. Your machine, type C, first ran at 60 feet per minute, later at 90. For the sound film, which also involved machine development, the performance of the copying machines was increased to 180 feet per minute. That corresponds to 48 frames or 0.912 m per second. Since 1990 there have been copier machines that run continuously at 480 g / s (9.12 m per second).

After the Second World War, diversification to multi-head machines took place, because multi-volume mounted film also requires economic efficiency. New film formats made appropriate copying machines necessary: Cinerama , Todd-AO , VistaVision , CinemaScope 55, Techniscope , IMAX .

A further distinction is made between ordinary copier machines, which are set up in a darkened room, and daylight machines with light-tight film magazines and doors. There are, on the other hand, copier machines for “dry” and “wet” work, the latter of which dips the film material into a special liquid or is wetted by it. The refractive index of the copying liquid is close to that of the film base or the image layer. This reduces the visibility of scratches in the film material.

Some copy machine builders

  • Paul Rademacher, Berlin
  • Ets André Debrie , Paris
  • Bell & Howell Co., Chicago
  • Arnold & Richter, Kg., Munich
  • Agfa, Leverkusen
  • Walturdaw, London
  • Lawley, London
  • Linwood Gale Dunn
  • Karl August Geyer, Berlin
  • Union, Ag., Berlin
  • Peterson
  • Uhler Cine Machine Co., Detroit MI
  • TOBIS (TONBILD-SYNDIKAT), GmbH, Berlin
  • Mitchell Camera Corporation, Glendale CA.
  • Seiki, Tokyo